<!DOCTYPE html>
<html lang="zh-CN">
  <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width,initial-scale=1">
    <title>CY博客 | 前端分享</title>
    <meta name="description" content="Vite & Vue powered static site generator.">
    <link rel="preload stylesheet" href="/docs/assets/style.ddc933c3.css" as="style">
    <link rel="modulepreload" href="/docs/assets/app.c4198e49.js">
    <link rel="modulepreload" href="/docs/assets/frontend_qf_JS循环对象.md.79b4e37f.lean.js">
    
    <script id="check-dark-light">(()=>{const e=localStorage.getItem("vitepress-theme-appearance")||"",a=window.matchMedia("(prefers-color-scheme: dark)").matches;(!e||e==="auto"?a:e==="dark")&&document.documentElement.classList.add("dark")})();</script>
  </head>
  <body>
    <div id="app"><div class="Layout" data-v-5211c0b1><!--[--><!--]--><!--[--><span tabindex="-1" data-v-151f2593></span><a href="#VPContent" class="VPSkipLink visually-hidden" data-v-151f2593> Skip to content </a><!--]--><!----><header class="VPNav" data-v-5211c0b1 data-v-8c0a9870><div class="VPNavBar has-sidebar" data-v-8c0a9870 data-v-1bbed88e><div class="container" data-v-1bbed88e><div class="VPNavBarTitle has-sidebar" data-v-1bbed88e data-v-d5925166><a class="title" href="/docs/" data-v-d5925166><!--[--><!--]--><!--[--><img class="VPImage logo" src="/docs/logo.jpg" alt data-v-6db2186b><!--]--><!--[-->CY博客<!--]--><!--[--><!--]--></a></div><div class="content" data-v-1bbed88e><!--[--><!--]--><!----><nav aria-labelledby="main-nav-aria-label" class="VPNavBarMenu menu" data-v-1bbed88e data-v-f83db6ba><span id="main-nav-aria-label" class="visually-hidden" data-v-f83db6ba>Main Navigation</span><!--[--><!--[--><a class="VPLink link VPNavBarMenuLink" href="/docs/" data-v-f83db6ba data-v-47a2263e data-v-3c355974><!--[-->首页<!--]--><!----></a><!--]--><!--[--><a class="VPLink link VPNavBarMenuLink" href="/docs/about/" data-v-f83db6ba data-v-47a2263e data-v-3c355974><!--[-->关于<!--]--><!----></a><!--]--><!--[--><a class="VPLink link VPNavBarMenuLink" href="/docs/frontend/" data-v-f83db6ba data-v-47a2263e data-v-3c355974><!--[-->前端<!--]--><!----></a><!--]--><!--]--></nav><!----><div class="VPNavBarAppearance appearance" data-v-1bbed88e data-v-a3e7452b><button class="VPSwitch VPSwitchAppearance" type="button" role="switch" aria-label="toggle dark mode" aria-checked="false" data-v-a3e7452b data-v-481098f9 data-v-eba7420e><span class="check" data-v-eba7420e><span class="icon" data-v-eba7420e><!--[--><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="sun" data-v-481098f9><path d="M12,18c-3.3,0-6-2.7-6-6s2.7-6,6-6s6,2.7,6,6S15.3,18,12,18zM12,8c-2.2,0-4,1.8-4,4c0,2.2,1.8,4,4,4c2.2,0,4-1.8,4-4C16,9.8,14.2,8,12,8z"></path><path d="M12,4c-0.6,0-1-0.4-1-1V1c0-0.6,0.4-1,1-1s1,0.4,1,1v2C13,3.6,12.6,4,12,4z"></path><path d="M12,24c-0.6,0-1-0.4-1-1v-2c0-0.6,0.4-1,1-1s1,0.4,1,1v2C13,23.6,12.6,24,12,24z"></path><path d="M5.6,6.6c-0.3,0-0.5-0.1-0.7-0.3L3.5,4.9c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l1.4,1.4c0.4,0.4,0.4,1,0,1.4C6.2,6.5,5.9,6.6,5.6,6.6z"></path><path d="M19.8,20.8c-0.3,0-0.5-0.1-0.7-0.3l-1.4-1.4c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l1.4,1.4c0.4,0.4,0.4,1,0,1.4C20.3,20.7,20,20.8,19.8,20.8z"></path><path d="M3,13H1c-0.6,0-1-0.4-1-1s0.4-1,1-1h2c0.6,0,1,0.4,1,1S3.6,13,3,13z"></path><path d="M23,13h-2c-0.6,0-1-0.4-1-1s0.4-1,1-1h2c0.6,0,1,0.4,1,1S23.6,13,23,13z"></path><path d="M4.2,20.8c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l1.4-1.4c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-1.4,1.4C4.7,20.7,4.5,20.8,4.2,20.8z"></path><path d="M18.4,6.6c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l1.4-1.4c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-1.4,1.4C18.9,6.5,18.6,6.6,18.4,6.6z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="moon" data-v-481098f9><path d="M12.1,22c-0.3,0-0.6,0-0.9,0c-5.5-0.5-9.5-5.4-9-10.9c0.4-4.8,4.2-8.6,9-9c0.4,0,0.8,0.2,1,0.5c0.2,0.3,0.2,0.8-0.1,1.1c-2,2.7-1.4,6.4,1.3,8.4c2.1,1.6,5,1.6,7.1,0c0.3-0.2,0.7-0.3,1.1-0.1c0.3,0.2,0.5,0.6,0.5,1c-0.2,2.7-1.5,5.1-3.6,6.8C16.6,21.2,14.4,22,12.1,22zM9.3,4.4c-2.9,1-5,3.6-5.2,6.8c-0.4,4.4,2.8,8.3,7.2,8.7c2.1,0.2,4.2-0.4,5.8-1.8c1.1-0.9,1.9-2.1,2.4-3.4c-2.5,0.9-5.3,0.5-7.5-1.1C9.2,11.4,8.1,7.7,9.3,4.4z"></path></svg><!--]--></span></span></button></div><div class="VPSocialLinks VPNavBarSocialLinks social-links" data-v-1bbed88e data-v-738bef5a data-v-f6988cfb><!--[--><a class="VPSocialLink" href="https://github.com/iyyo" target="_blank" rel="noopener" data-v-f6988cfb data-v-e57698f6><svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>GitHub</title><path d="M12 .297c-6.63 0-12 5.373-12 12 0 5.303 3.438 9.8 8.205 11.385.6.113.82-.258.82-.577 0-.285-.01-1.04-.015-2.04-3.338.724-4.042-1.61-4.042-1.61C4.422 18.07 3.633 17.7 3.633 17.7c-1.087-.744.084-.729.084-.729 1.205.084 1.838 1.236 1.838 1.236 1.07 1.835 2.809 1.305 3.495.998.108-.776.417-1.305.76-1.605-2.665-.3-5.466-1.332-5.466-5.93 0-1.31.465-2.38 1.235-3.22-.135-.303-.54-1.523.105-3.176 0 0 1.005-.322 3.3 1.23.96-.267 1.98-.399 3-.405 1.02.006 2.04.138 3 .405 2.28-1.552 3.285-1.23 3.285-1.23.645 1.653.24 2.873.12 3.176.765.84 1.23 1.91 1.23 3.22 0 4.61-2.805 5.625-5.475 5.92.42.36.81 1.096.81 2.22 0 1.606-.015 2.896-.015 3.286 0 .315.21.69.825.57C20.565 22.092 24 17.592 24 12.297c0-6.627-5.373-12-12-12"/></svg></a><!--]--></div><div class="VPFlyout VPNavBarExtra extra" data-v-1bbed88e data-v-e4361c82 data-v-6ffb57d3><button type="button" class="button" aria-haspopup="true" aria-expanded="false" aria-label="extra navigation" data-v-6ffb57d3><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="icon" data-v-6ffb57d3><circle cx="12" cy="12" r="2"></circle><circle cx="19" cy="12" r="2"></circle><circle cx="5" cy="12" r="2"></circle></svg></button><div class="menu" data-v-6ffb57d3><div class="VPMenu" data-v-6ffb57d3 data-v-1c5d0cfc><!----><!--[--><!--[--><!----><div class="group" data-v-e4361c82><div class="item appearance" data-v-e4361c82><p class="label" data-v-e4361c82>Appearance</p><div class="appearance-action" data-v-e4361c82><button class="VPSwitch VPSwitchAppearance" type="button" role="switch" aria-label="toggle dark mode" aria-checked="false" data-v-e4361c82 data-v-481098f9 data-v-eba7420e><span class="check" data-v-eba7420e><span class="icon" data-v-eba7420e><!--[--><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="sun" data-v-481098f9><path d="M12,18c-3.3,0-6-2.7-6-6s2.7-6,6-6s6,2.7,6,6S15.3,18,12,18zM12,8c-2.2,0-4,1.8-4,4c0,2.2,1.8,4,4,4c2.2,0,4-1.8,4-4C16,9.8,14.2,8,12,8z"></path><path d="M12,4c-0.6,0-1-0.4-1-1V1c0-0.6,0.4-1,1-1s1,0.4,1,1v2C13,3.6,12.6,4,12,4z"></path><path d="M12,24c-0.6,0-1-0.4-1-1v-2c0-0.6,0.4-1,1-1s1,0.4,1,1v2C13,23.6,12.6,24,12,24z"></path><path d="M5.6,6.6c-0.3,0-0.5-0.1-0.7-0.3L3.5,4.9c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l1.4,1.4c0.4,0.4,0.4,1,0,1.4C6.2,6.5,5.9,6.6,5.6,6.6z"></path><path d="M19.8,20.8c-0.3,0-0.5-0.1-0.7-0.3l-1.4-1.4c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l1.4,1.4c0.4,0.4,0.4,1,0,1.4C20.3,20.7,20,20.8,19.8,20.8z"></path><path d="M3,13H1c-0.6,0-1-0.4-1-1s0.4-1,1-1h2c0.6,0,1,0.4,1,1S3.6,13,3,13z"></path><path d="M23,13h-2c-0.6,0-1-0.4-1-1s0.4-1,1-1h2c0.6,0,1,0.4,1,1S23.6,13,23,13z"></path><path d="M4.2,20.8c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l1.4-1.4c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-1.4,1.4C4.7,20.7,4.5,20.8,4.2,20.8z"></path><path d="M18.4,6.6c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l1.4-1.4c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-1.4,1.4C18.9,6.5,18.6,6.6,18.4,6.6z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="moon" data-v-481098f9><path d="M12.1,22c-0.3,0-0.6,0-0.9,0c-5.5-0.5-9.5-5.4-9-10.9c0.4-4.8,4.2-8.6,9-9c0.4,0,0.8,0.2,1,0.5c0.2,0.3,0.2,0.8-0.1,1.1c-2,2.7-1.4,6.4,1.3,8.4c2.1,1.6,5,1.6,7.1,0c0.3-0.2,0.7-0.3,1.1-0.1c0.3,0.2,0.5,0.6,0.5,1c-0.2,2.7-1.5,5.1-3.6,6.8C16.6,21.2,14.4,22,12.1,22zM9.3,4.4c-2.9,1-5,3.6-5.2,6.8c-0.4,4.4,2.8,8.3,7.2,8.7c2.1,0.2,4.2-0.4,5.8-1.8c1.1-0.9,1.9-2.1,2.4-3.4c-2.5,0.9-5.3,0.5-7.5-1.1C9.2,11.4,8.1,7.7,9.3,4.4z"></path></svg><!--]--></span></span></button></div></div></div><div class="group" data-v-e4361c82><div class="item social-links" data-v-e4361c82><div class="VPSocialLinks social-links-list" data-v-e4361c82 data-v-f6988cfb><!--[--><a class="VPSocialLink" href="https://github.com/iyyo" target="_blank" rel="noopener" data-v-f6988cfb data-v-e57698f6><svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>GitHub</title><path d="M12 .297c-6.63 0-12 5.373-12 12 0 5.303 3.438 9.8 8.205 11.385.6.113.82-.258.82-.577 0-.285-.01-1.04-.015-2.04-3.338.724-4.042-1.61-4.042-1.61C4.422 18.07 3.633 17.7 3.633 17.7c-1.087-.744.084-.729.084-.729 1.205.084 1.838 1.236 1.838 1.236 1.07 1.835 2.809 1.305 3.495.998.108-.776.417-1.305.76-1.605-2.665-.3-5.466-1.332-5.466-5.93 0-1.31.465-2.38 1.235-3.22-.135-.303-.54-1.523.105-3.176 0 0 1.005-.322 3.3 1.23.96-.267 1.98-.399 3-.405 1.02.006 2.04.138 3 .405 2.28-1.552 3.285-1.23 3.285-1.23.645 1.653.24 2.873.12 3.176.765.84 1.23 1.91 1.23 3.22 0 4.61-2.805 5.625-5.475 5.92.42.36.81 1.096.81 2.22 0 1.606-.015 2.896-.015 3.286 0 .315.21.69.825.57C20.565 22.092 24 17.592 24 12.297c0-6.627-5.373-12-12-12"/></svg></a><!--]--></div></div></div><!--]--><!--]--></div></div></div><!--[--><!--]--><button type="button" class="VPNavBarHamburger hamburger" aria-label="mobile navigation" aria-expanded="false" aria-controls="VPNavScreen" data-v-1bbed88e data-v-e5dd9c1c><span class="container" data-v-e5dd9c1c><span class="top" data-v-e5dd9c1c></span><span class="middle" data-v-e5dd9c1c></span><span class="bottom" data-v-e5dd9c1c></span></span></button></div></div></div><!----></header><div class="VPLocalNav" data-v-5211c0b1 data-v-b6162a8b><button class="menu" aria-expanded="false" aria-controls="VPSidebarNav" data-v-b6162a8b><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="menu-icon" data-v-b6162a8b><path d="M17,11H3c-0.6,0-1-0.4-1-1s0.4-1,1-1h14c0.6,0,1,0.4,1,1S17.6,11,17,11z"></path><path d="M21,7H3C2.4,7,2,6.6,2,6s0.4-1,1-1h18c0.6,0,1,0.4,1,1S21.6,7,21,7z"></path><path d="M21,15H3c-0.6,0-1-0.4-1-1s0.4-1,1-1h18c0.6,0,1,0.4,1,1S21.6,15,21,15z"></path><path d="M17,19H3c-0.6,0-1-0.4-1-1s0.4-1,1-1h14c0.6,0,1,0.4,1,1S17.6,19,17,19z"></path></svg><span class="menu-text" data-v-b6162a8b>Menu</span></button><a class="top-link" href="#" data-v-b6162a8b> Return to top </a></div><aside class="VPSidebar" data-v-5211c0b1 data-v-a186aa16><nav class="nav" id="VPSidebarNav" aria-labelledby="sidebar-aria-label" tabindex="-1" data-v-a186aa16><span class="visually-hidden" id="sidebar-aria-label" data-v-a186aa16> Sidebar Navigation </span><!--[--><!--]--><!--[--><div class="group" data-v-a186aa16><section class="VPSidebarGroup collapsible collapsed" data-v-a186aa16 data-v-6e45c352><div class="title" role="button" data-v-6e45c352><h2 class="title-text" data-v-6e45c352>HTML学习</h2><div class="action" data-v-6e45c352><svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewbox="0 0 24 24" class="icon minus" data-v-6e45c352><path d="M19,2H5C3.3,2,2,3.3,2,5v14c0,1.7,1.3,3,3,3h14c1.7,0,3-1.3,3-3V5C22,3.3,20.7,2,19,2zM20,19c0,0.6-0.4,1-1,1H5c-0.6,0-1-0.4-1-1V5c0-0.6,0.4-1,1-1h14c0.6,0,1,0.4,1,1V19z"></path><path d="M16,11H8c-0.6,0-1,0.4-1,1s0.4,1,1,1h8c0.6,0,1-0.4,1-1S16.6,11,16,11z"></path></svg><svg version="1.1" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 24 24" class="icon plus" data-v-6e45c352><path d="M19,2H5C3.3,2,2,3.3,2,5v14c0,1.7,1.3,3,3,3h14c1.7,0,3-1.3,3-3V5C22,3.3,20.7,2,19,2z M20,19c0,0.6-0.4,1-1,1H5c-0.6,0-1-0.4-1-1V5c0-0.6,0.4-1,1-1h14c0.6,0,1,0.4,1,1V19z"></path><path d="M16,11h-3V8c0-0.6-0.4-1-1-1s-1,0.4-1,1v3H8c-0.6,0-1,0.4-1,1s0.4,1,1,1h3v3c0,0.6,0.4,1,1,1s1-0.4,1-1v-3h3c0.6,0,1-0.4,1-1S16.6,11,16,11z"></path></svg></div></div><div class="items" data-v-6e45c352><!--[--><!--[--><a class="VPLink link link" href="/docs/frontend/html/" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>html基础</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/html/%E6%A0%87%E7%AD%BE%E5%AD%A6%E4%B9%A0.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>html标签学习</span><!--]--><!----></a><!----><!--]--><!--]--></div></section></div><div class="group" data-v-a186aa16><section class="VPSidebarGroup collapsible collapsed" data-v-a186aa16 data-v-6e45c352><div class="title" role="button" data-v-6e45c352><h2 class="title-text" data-v-6e45c352>JavaScript教程</h2><div class="action" data-v-6e45c352><svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewbox="0 0 24 24" class="icon minus" data-v-6e45c352><path d="M19,2H5C3.3,2,2,3.3,2,5v14c0,1.7,1.3,3,3,3h14c1.7,0,3-1.3,3-3V5C22,3.3,20.7,2,19,2zM20,19c0,0.6-0.4,1-1,1H5c-0.6,0-1-0.4-1-1V5c0-0.6,0.4-1,1-1h14c0.6,0,1,0.4,1,1V19z"></path><path d="M16,11H8c-0.6,0-1,0.4-1,1s0.4,1,1,1h8c0.6,0,1-0.4,1-1S16.6,11,16,11z"></path></svg><svg version="1.1" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 24 24" class="icon plus" data-v-6e45c352><path d="M19,2H5C3.3,2,2,3.3,2,5v14c0,1.7,1.3,3,3,3h14c1.7,0,3-1.3,3-3V5C22,3.3,20.7,2,19,2z M20,19c0,0.6-0.4,1-1,1H5c-0.6,0-1-0.4-1-1V5c0-0.6,0.4-1,1-1h14c0.6,0,1,0.4,1,1V19z"></path><path d="M16,11h-3V8c0-0.6-0.4-1-1-1s-1,0.4-1,1v3H8c-0.6,0-1,0.4-1,1s0.4,1,1,1h3v3c0,0.6,0.4,1,1,1s1-0.4,1-1v-3h3c0.6,0,1-0.4,1-1S16.6,11,16,11z"></path></svg></div></div><div class="items" data-v-6e45c352><!--[--><!--[--><a class="VPLink link link" href="/docs/frontend/js/JavaScript%E7%9A%84%E5%9F%BA%E7%A1%80%E8%AF%AD%E6%B3%95.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>基础语法</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/%E5%88%86%E6%94%AF%E7%BB%93%E6%9E%84.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>分支结构</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/%E5%BE%AA%E7%8E%AF%E7%BB%93%E6%9E%84.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>循环结构</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/%E5%87%BD%E6%95%B0(%E4%B8%8A).html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>函数（上）</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/%E5%87%BD%E6%95%B0%EF%BC%88%E4%B8%8B%EF%BC%89.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>函数（下）</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/%E6%95%B0%E7%BB%84.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>数组</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/%E5%AD%97%E7%AC%A6%E4%B8%B2%E7%9A%84%E6%93%8D%E4%BD%9C.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>字符串的操作</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/Math%E5%92%8CDate.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>Math和Date</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/BOM%E5%92%8CDOM%EF%BC%88%E4%B8%8A%EF%BC%89.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>BOM和DOM（上）</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/js/DOM%EF%BC%88%E4%B8%8B%EF%BC%89.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>DOM（下）</span><!--]--><!----></a><!----><!--]--><!--]--></div></section></div><div class="group" data-v-a186aa16><section class="VPSidebarGroup collapsible collapsed" data-v-a186aa16 data-v-6e45c352><div class="title" role="button" data-v-6e45c352><h2 class="title-text" data-v-6e45c352>千锋线下学习</h2><div class="action" data-v-6e45c352><svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewbox="0 0 24 24" class="icon minus" data-v-6e45c352><path d="M19,2H5C3.3,2,2,3.3,2,5v14c0,1.7,1.3,3,3,3h14c1.7,0,3-1.3,3-3V5C22,3.3,20.7,2,19,2zM20,19c0,0.6-0.4,1-1,1H5c-0.6,0-1-0.4-1-1V5c0-0.6,0.4-1,1-1h14c0.6,0,1,0.4,1,1V19z"></path><path d="M16,11H8c-0.6,0-1,0.4-1,1s0.4,1,1,1h8c0.6,0,1-0.4,1-1S16.6,11,16,11z"></path></svg><svg version="1.1" xmlns="http://www.w3.org/2000/svg" viewbox="0 0 24 24" class="icon plus" data-v-6e45c352><path d="M19,2H5C3.3,2,2,3.3,2,5v14c0,1.7,1.3,3,3,3h14c1.7,0,3-1.3,3-3V5C22,3.3,20.7,2,19,2z M20,19c0,0.6-0.4,1-1,1H5c-0.6,0-1-0.4-1-1V5c0-0.6,0.4-1,1-1h14c0.6,0,1,0.4,1,1V19z"></path><path d="M16,11h-3V8c0-0.6-0.4-1-1-1s-1,0.4-1,1v3H8c-0.6,0-1,0.4-1,1s0.4,1,1,1h3v3c0,0.6,0.4,1,1,1s1-0.4,1-1v-3h3c0.6,0,1-0.4,1-1S16.6,11,16,11z"></path></svg></div></div><div class="items" data-v-6e45c352><!--[--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JS%E8%BF%90%E7%AE%97%E7%AC%A6.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JS运算符</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JS%E5%BE%AA%E7%8E%AF%E5%AF%B9%E8%B1%A1.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JS循环对象</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JS%E5%87%BD%E6%95%B0.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JS函数</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JS%E5%AF%B9%E8%B1%A1.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JS对象</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JS%E6%95%B0%E7%BB%84%E9%87%8D%E6%9E%84.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JS数组重构</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JS%E6%95%B0%E7%BB%84%E9%87%8D%E6%9E%842.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JS数组重构2</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JS%E8%B7%AF%E7%94%B1.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JS路由</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JSDOM.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JSDOM知识</span><!--]--><!----></a><!----><!--]--><!--[--><a class="VPLink link link" href="/docs/frontend/qf/JS%E4%BA%8B%E4%BB%B6.html" style="padding-left:0px;" tabindex="-1" data-v-70e2cdfb data-v-3c355974><!--[--><span class="link-text" data-v-70e2cdfb>JS事件</span><!--]--><!----></a><!----><!--]--><!--]--></div></section></div><!--]--><!--[--><!--]--></nav></aside><div class="VPContent has-sidebar" id="VPContent" data-v-5211c0b1 data-v-296cfad2><div class="VPDoc has-sidebar has-aside" data-v-296cfad2 data-v-cfb513e0><div class="container" data-v-cfb513e0><div class="aside" data-v-cfb513e0><div class="aside-curtain" data-v-cfb513e0></div><div class="aside-container" data-v-cfb513e0><div class="aside-content" data-v-cfb513e0><div class="VPDocAside" data-v-cfb513e0 data-v-afc4c1a1><!--[--><!--]--><!--[--><!--]--><div class="VPDocAsideOutline" data-v-afc4c1a1 data-v-2865c0b0><div class="content" data-v-2865c0b0><div class="outline-marker" data-v-2865c0b0></div><div class="outline-title" data-v-2865c0b0>On this page</div><nav aria-labelledby="doc-outline-aria-label" data-v-2865c0b0><span class="visually-hidden" id="doc-outline-aria-label" data-v-2865c0b0> Table of Contents for current page </span><ul class="root" data-v-2865c0b0 data-v-1188541a><!--[--><!--]--></ul></nav></div></div><!--[--><!--]--><div class="spacer" data-v-afc4c1a1></div><!--[--><!--]--><!----><!--[--><!--]--><!--[--><!--]--></div></div></div></div><div class="content" data-v-cfb513e0><div class="content-container" data-v-cfb513e0><!--[--><!--]--><main class="main" data-v-cfb513e0><div style="position:relative;" class="vp-doc _docs_frontend_qf_JS%E5%BE%AA%E7%8E%AF%E5%AF%B9%E8%B1%A1" data-v-cfb513e0><div><h4 id="while循环" tabindex="-1">while循环 <a class="header-anchor" href="#while循环" aria-hidden="true">#</a></h4><ul><li><p>特点：会造成死循环</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#676E95;font-style:italic;">// 条件语句到达目标值</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> i </span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">0</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> sum </span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">0</span></span>
<span class="line"><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;">(i</span><span style="color:#89DDFF;">&lt;=</span><span style="color:#F78C6C;">100</span><span style="color:#A6ACCD;">)</span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#A6ACCD;">sum</span><span style="color:#89DDFF;">+=</span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;">	</span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">++</span><span style="color:#F07178;">		</span><span style="color:#676E95;font-style:italic;">// 递进值</span></span>
<span class="line"><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(sum)	</span><span style="color:#676E95;font-style:italic;">// 5050</span></span>
<span class="line"></span>
<span class="line"><span style="color:#82AAFF;">white</span><span style="color:#A6ACCD;">(表达式)		</span><span style="color:#676E95;font-style:italic;">// 隐士转换表达式为布尔值，true进入，false跳出</span></span>
<span class="line"></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> i</span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">0</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> s</span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">0</span><span style="color:#A6ACCD;">	</span><span style="color:#676E95;font-style:italic;">// 避免在使用的时候出现死循环</span></span>
<span class="line"><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;">(i</span><span style="color:#89DDFF;">++&lt;</span><span style="color:#F78C6C;">100</span><span style="color:#A6ACCD;">)</span><span style="color:#89DDFF;">{</span><span style="color:#F07178;">	</span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#A6ACCD;">s</span><span style="color:#89DDFF;">+=</span><span style="color:#A6ACCD;">i</span></span>
<span class="line"><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(s)	</span><span style="color:#676E95;font-style:italic;">// 5050</span></span>
<span class="line"></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> s</span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">0</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">0</span></span>
<span class="line"><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;">(i</span><span style="color:#89DDFF;">++,</span><span style="color:#A6ACCD;">s</span><span style="color:#89DDFF;">+=</span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">&lt;=</span><span style="color:#F78C6C;">100</span><span style="color:#A6ACCD;">)	</span><span style="color:#676E95;font-style:italic;">// 使用;结束循环,因为没有循环体必须使用</span></span>
<span class="line"><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(s)  </span><span style="color:#676E95;font-style:italic;">// 5050</span></span>
<span class="line"></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// break跳出循环</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> i</span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">0</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">s</span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">0</span></span>
<span class="line"><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;">(</span><span style="color:#F78C6C;">1</span><span style="color:#A6ACCD;">)</span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#89DDFF;font-style:italic;">if</span><span style="color:#F07178;">(</span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">&gt;</span><span style="color:#F78C6C;">100</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;font-style:italic;">break</span><span style="color:#F07178;">		</span><span style="color:#676E95;font-style:italic;">// 将跳出循环的条件写在循环体内	</span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#A6ACCD;">s</span><span style="color:#89DDFF;">+=</span><span style="color:#A6ACCD;">i</span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">++</span></span>
<span class="line"><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(s)</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br></div></div><ul><li>注意: <ul><li>while循环中使用,每次都会执行,但是最后一个,之后的的内容才做为判断,之前的不作为判断</li><li>循环的条件可以是一个死循环.永远为真 eg:while(1){} while(true){}</li><li><code>死循环</code>搭配break使用</li></ul></li></ul></li><li><p>嵌套循环</p><ul><li>break label</li></ul><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> i </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">0</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> j </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">0</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#FFCB6B;">abc</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;"> (i </span><span style="color:#89DDFF;">&lt;</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">10</span><span style="color:#A6ACCD;">) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">=</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">0</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&lt;</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">10</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#89DDFF;">                </span><span style="color:#676E95;font-style:italic;">// 只要两数相乘就跳出循环</span></span>
<span class="line"><span style="color:#F07178;">                </span><span style="color:#89DDFF;font-style:italic;">if</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">*</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&gt;</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">50</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;font-style:italic;">break</span><span style="color:#F07178;"> </span><span style="color:#FFCB6B;">abc</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">                </span><span style="color:#A6ACCD;">j</span><span style="color:#89DDFF;">++</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">++</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(i </span><span style="color:#89DDFF;">*</span><span style="color:#A6ACCD;"> j</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> i</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> j)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(</span><span style="color:#89DDFF;">&quot;</span><span style="color:#C3E88D;">完成</span><span style="color:#89DDFF;">&quot;</span><span style="color:#A6ACCD;">)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br></div></div><ul><li><p>continue label</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> str </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&#39;</span><span style="color:#C3E88D;">&lt;table&gt;</span><span style="color:#89DDFF;">&#39;</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> i </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">0</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> j </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#FFCB6B;">ab</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;"> (i</span><span style="color:#89DDFF;">++</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&lt;</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">9</span><span style="color:#A6ACCD;">) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">str</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">+=</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&#39;</span><span style="color:#C3E88D;">&lt;tr&gt;</span><span style="color:#89DDFF;">&#39;</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">=</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">1</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#F07178;"> (</span><span style="color:#F78C6C;">1</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">                </span><span style="color:#89DDFF;font-style:italic;">if</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&gt;</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;font-style:italic;">continue</span><span style="color:#F07178;"> </span><span style="color:#FFCB6B;">ab</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">                </span><span style="color:#A6ACCD;">str</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">+=</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&#39;</span><span style="color:#C3E88D;">&lt;td&gt;</span><span style="color:#89DDFF;">&#39;</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">+</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">*</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">10</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">+</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;">+</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&#39;</span><span style="color:#C3E88D;">&lt;/td&gt;</span><span style="color:#89DDFF;">&#39;</span></span>
<span class="line"><span style="color:#F07178;">                </span><span style="color:#A6ACCD;">j</span><span style="color:#89DDFF;">++</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">str</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">+=</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&#39;</span><span style="color:#C3E88D;">&lt;/tr&gt;</span><span style="color:#89DDFF;">&#39;</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">++</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">        str </span><span style="color:#89DDFF;">+=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&#39;</span><span style="color:#C3E88D;">&lt;/table&gt;</span><span style="color:#89DDFF;">&#39;</span></span>
<span class="line"><span style="color:#A6ACCD;">        document</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">body</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">innerHTML </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> str</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br></div></div></li></ul></li><li><p>遍历</p><ul><li><p>广度遍历 - 使用For循环</p></li><li><p>深度遍历 - 使用递归</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> linked </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#F07178;">value</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">,</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#F07178;">next</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#A6ACCD;">                </span><span style="color:#F07178;">value</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">2</span><span style="color:#89DDFF;">,</span></span>
<span class="line"><span style="color:#A6ACCD;">                </span><span style="color:#F07178;">next</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#A6ACCD;">                    </span><span style="color:#F07178;">value</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">3</span><span style="color:#89DDFF;">,</span></span>
<span class="line"><span style="color:#A6ACCD;">                    </span><span style="color:#F07178;">next</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#A6ACCD;">                        </span><span style="color:#F07178;">value</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">4</span><span style="color:#89DDFF;">,</span></span>
<span class="line"><span style="color:#A6ACCD;">                        </span><span style="color:#F07178;">next</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#A6ACCD;">                            </span><span style="color:#F07178;">value</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">5</span><span style="color:#89DDFF;">,</span></span>
<span class="line"><span style="color:#A6ACCD;">                            </span><span style="color:#F07178;">next</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">null</span></span>
<span class="line"><span style="color:#A6ACCD;">                        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">                    </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">                </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;"> (linked) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#F07178;">(</span><span style="color:#A6ACCD;">linked</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">value</span><span style="color:#F07178;">)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">linked</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">=</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">linked</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">next</span><span style="color:#89DDFF;">;</span><span style="color:#F07178;">   </span><span style="color:#676E95;font-style:italic;">// 不添加这个就会死循环</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br></div></div></li></ul></li></ul><h4 id="do-while" tabindex="-1">Do While <a class="header-anchor" href="#do-while" aria-hidden="true">#</a></h4><ul><li><p>表格式格式</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#89DDFF;font-style:italic;">do</span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#89DDFF;">    </span><span style="color:#676E95;font-style:italic;">// 语句块</span></span>
<span class="line"><span style="color:#89DDFF;">}</span><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;">(表达式;用于进入循环的条件)</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 先执行语句块内容,然后判断条件,如果表达式满足条件,则重新执行语句块</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 一般表达式作为进入循环的条件,而语句块中会使用break来处理跳出的条件</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br></div></div><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#FFCB6B;">eg</span><span style="color:#89DDFF;">:</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> i </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">0</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;font-style:italic;">do</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">+=</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">3</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;font-style:italic;">if</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&gt;</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">10</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;font-style:italic;">break</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;"> (i </span><span style="color:#89DDFF;">&gt;</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">2</span><span style="color:#A6ACCD;">)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(i)</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> arr </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> [</span><span style="color:#F78C6C;">0</span><span style="color:#A6ACCD;">]</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;font-style:italic;">do</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">arr</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">push</span><span style="color:#F07178;">(</span><span style="color:#F78C6C;">1</span><span style="color:#F07178;">)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;font-style:italic;">if</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">arr</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">length</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&gt;</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">10</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;font-style:italic;">break</span><span style="color:#89DDFF;">;</span></span>
<span class="line"></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;font-style:italic;">while</span><span style="color:#A6ACCD;"> (arr</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">length </span><span style="color:#89DDFF;">&gt;</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#A6ACCD;">)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(arr)</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br></div></div></li></ul><h4 id="for循环" tabindex="-1">For循环 <a class="header-anchor" href="#for循环" aria-hidden="true">#</a></h4><ul><li><p>格式:</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#676E95;font-style:italic;">// 初始值部分   只执行一次,尽量让这个初始化部分变量作为私有局部变量的存在</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 条件部分		满足条件进入循环  可以使用逻辑与和逻辑或放入多个条件,但是如果使用,分割 条件只是最后逗号后面的部分</span></span>
<span class="line"><span style="color:#89DDFF;">			</span><span style="color:#676E95;font-style:italic;">// 每次开始的时候的都会执行</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 循环向条件外变化的表达式		可以使用逗号分割写入多个表达式,每次循环都会执行,每次循环的语句执行完成后执行</span></span>
<span class="line"><span style="color:#89DDFF;">						</span><span style="color:#676E95;font-style:italic;">//  当执行continue时,会在continue跳出后执行</span></span>
<span class="line"><span style="color:#89DDFF;font-style:italic;">for</span><span style="color:#A6ACCD;">(初始值部分</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">条件部分</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">循环向条件外变化的表达式)</span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">	    </span></span>
<span class="line"><span style="color:#89DDFF;">}</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br></div></div><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#676E95;font-style:italic;">// 计算100以内的和</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;font-style:italic;">for</span><span style="color:#A6ACCD;"> (</span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> i </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">0</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> sum </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">0</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> i </span><span style="color:#89DDFF;">&lt;=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">100</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> sum </span><span style="color:#89DDFF;">+=</span><span style="color:#A6ACCD;"> i</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> i</span><span style="color:#89DDFF;">++</span><span style="color:#A6ACCD;">) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#F07178;">(</span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;">)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 实现100以内的素数判断</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#FFCB6B;">abc</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;font-style:italic;">for</span><span style="color:#A6ACCD;"> (</span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> i </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">2</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> j</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> i </span><span style="color:#89DDFF;">&lt;</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">100</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> i</span><span style="color:#89DDFF;">++</span><span style="color:#A6ACCD;">) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;font-style:italic;">for</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">=</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">2</span><span style="color:#89DDFF;">;</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&lt;</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">i</span><span style="color:#89DDFF;">;</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">j</span><span style="color:#89DDFF;">++</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">                </span><span style="color:#89DDFF;font-style:italic;">if</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">%</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">j</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">===</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">0</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;font-style:italic;">continue</span><span style="color:#F07178;"> </span><span style="color:#FFCB6B;">abc</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#F07178;">(</span><span style="color:#A6ACCD;">i</span><span style="color:#F07178;">)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 输出数组</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> arr </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> []</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;font-style:italic;">for</span><span style="color:#A6ACCD;"> (</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#89DDFF;font-style:italic;">if</span><span style="color:#F07178;"> (</span><span style="color:#A6ACCD;">arr</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">length</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">&gt;</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">9</span><span style="color:#F07178;">) </span><span style="color:#89DDFF;font-style:italic;">break</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">arr</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">push</span><span style="color:#F07178;">(</span><span style="color:#F78C6C;">1</span><span style="color:#F07178;">)</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(arr)</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> </span><span style="color:#676E95;font-style:italic;">// (10) [1, 1, 1, 1, 1, 1, 1, 1, 1, 1]</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br></div></div></li></ul><h4 id="对象" tabindex="-1">对象 <a class="header-anchor" href="#对象" aria-hidden="true">#</a></h4><ul><li><p>字面量创建</p><ul><li><p>var o={}</p></li><li><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#676E95;font-style:italic;">// 对象中有一个名字,对应一个内容,这个内容可能是值,也可能是一个函数</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 值就是属性,函数就是方法</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// key:value  对象中是key,value是成对出现的,键值对</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 属性,可以给对象的属性中存储值,可以理解为这个值是这个对象私有的变量值	</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 方法,为当前对象设置的部分可执行的语句块,当执行这些方法时可以执行语句块内容这个方法就是这个对象的私有函数</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o</span><span style="color:#89DDFF;">={</span></span>
<span class="line"><span style="color:#A6ACCD;">    </span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">,</span></span>
<span class="line"><span style="color:#A6ACCD;">    </span><span style="color:#82AAFF;">b</span><span style="color:#89DDFF;">:</span><span style="color:#C792EA;">function</span><span style="color:#89DDFF;">(){</span></span>
<span class="line"><span style="color:#F07178;">        </span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#89DDFF;">}</span></span>
<span class="line"></span>
<span class="line"></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 键值对,键唯一,当前对象中的键名不能重复,值是可以重复的</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 通过该键名一定可以取到对应的值,这种方式用来快速查找一个值</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">// 对象在所有的数据结构是查找速度最快的数据类型</span></span>
<span class="line"></span>
<span class="line"><span style="color:#676E95;font-style:italic;">/*</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">	1. 属性名直接给,这个属性名就是字符串,定义要求与变量名定义要求相同,纯数字也是可以的</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">	2. 使用&quot;&quot;或者&#39;&#39; 引起来属性名,可以允许属性名中产生使用非法字符</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">    3. 使用[]设定属性名,[]给入两种内容,一种是使用&quot;&quot;或者&#39;&#39;引起的字符串/数值,第二种是变量名,这时候就会把变量值作为属性名,如果使用[]这种方式放入变量,这个变量值并不是字符串类型或者Symbol类型,则会自动隐士转换为字符串作为属性名</span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">    </span></span>
<span class="line"><span style="color:#676E95;font-style:italic;">*/</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> a </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&quot;</span><span style="color:#C3E88D;">art</span><span style="color:#89DDFF;">&quot;</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> c </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&#39;</span><span style="color:#C3E88D;">cat</span><span style="color:#89DDFF;">&#39;</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> obj </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">       </span><span style="color:#676E95;font-style:italic;">// a:1</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">a b</span><span style="color:#89DDFF;">&quot;</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">2</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">   </span><span style="color:#676E95;font-style:italic;">// a b:2</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#F07178;">[</span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">a-b</span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">]</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">3</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">     </span><span style="color:#676E95;font-style:italic;">// a-b:3</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#F07178;">[</span><span style="color:#F78C6C;">1</span><span style="color:#F07178;">]</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">4</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#676E95;font-style:italic;">// 1:4</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#F07178;">[</span><span style="color:#A6ACCD;">a</span><span style="color:#F07178;">]</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">9</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#676E95;font-style:italic;">// 变量会自动转换成字符串作为属性名  art:9</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#F07178;">[</span><span style="color:#A6ACCD;">c</span><span style="color:#F07178;">]</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">12</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">    </span><span style="color:#676E95;font-style:italic;">// cat:12</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(obj)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br><span class="line-number">23</span><br><span class="line-number">24</span><br><span class="line-number">25</span><br><span class="line-number">26</span><br><span class="line-number">27</span><br><span class="line-number">28</span><br><span class="line-number">29</span><br><span class="line-number">30</span><br><span class="line-number">31</span><br><span class="line-number">32</span><br><span class="line-number">33</span><br><span class="line-number">34</span><br><span class="line-number">35</span><br><span class="line-number">36</span><br></div></div></li><li><p>对象的获取</p><ul><li>js是 . 语法</li></ul><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> a </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&quot;</span><span style="color:#C3E88D;">art</span><span style="color:#89DDFF;">&quot;</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> obj </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">       </span><span style="color:#676E95;font-style:italic;">// a:1</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(obj</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">a)</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">	</span><span style="color:#676E95;font-style:italic;">// 1</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br></div></div></li><li><p>对象的类型</p><ul><li><p>字符型对象</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> a </span><span style="color:#89DDFF;">=new</span><span style="color:#A6ACCD;"> </span><span style="color:#82AAFF;">String</span><span style="color:#A6ACCD;">(</span><span style="color:#89DDFF;">&quot;</span><span style="color:#C3E88D;">a</span><span style="color:#89DDFF;">&quot;</span><span style="color:#A6ACCD;">)</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br></div></div></li><li><p>数值型对象</p><div class="language-javascript line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">javascript</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> b</span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">new</span><span style="color:#A6ACCD;"> </span><span style="color:#82AAFF;">Number</span><span style="color:#A6ACCD;">(</span><span style="color:#F78C6C;">1</span><span style="color:#A6ACCD;">)</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br></div></div></li><li><p>布尔型对象</p><div class="language-javascript line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">javascript</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> c </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">new</span><span style="color:#A6ACCD;"> </span><span style="color:#82AAFF;">Boolean</span><span style="color:#A6ACCD;">(</span><span style="color:#FF9CAC;">true</span><span style="color:#A6ACCD;">)</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br></div></div><blockquote><ol><li>当调用字符串方法/数值方法/布尔方法,会自动创建一个该对象类型,执行方法得到结果映射</li><li>该类型非法字符不能使用 . 语法</li><li>获取属性和设置属性不同于创建对象时,<code>不可以使用双引号和单引号</code></li><li>使用 <code>[]</code>来获取<code>非法字符</code>[&quot;a b&quot;]或者<code>变量</code>[ art ]属性</li></ol><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> obj </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">a b</span><span style="color:#89DDFF;">&quot;</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">,</span></span>
<span class="line"><span style="color:#A6ACCD;">            </span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">&amp;bcd</span><span style="color:#89DDFF;">&quot;</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">3</span><span style="color:#89DDFF;">,</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(obj[</span><span style="color:#89DDFF;">&quot;</span><span style="color:#C3E88D;">a b</span><span style="color:#89DDFF;">&quot;</span><span style="color:#A6ACCD;">])</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">    </span><span style="color:#676E95;font-style:italic;">// 1</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(obj[</span><span style="color:#89DDFF;">&quot;</span><span style="color:#C3E88D;">&amp;bcd</span><span style="color:#89DDFF;">&quot;</span><span style="color:#A6ACCD;">])</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">    </span><span style="color:#676E95;font-style:italic;">// 3</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br></div></div></blockquote></li></ul></li><li><p>引用对象</p><ul><li>如果两个变量引用的是同一个地址,这两个变量引用地址相同,当修改对象的属性时候,另一个变量看到的也是修改后的结果</li><li>如果将其中一个变量设置为新的对象, 这表示改变了引用地址,和另一个变量就产生了不同的区分,那另一个变量并不会发生改变</li></ul><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span><span style="color:#A6ACCD;"> </span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(o)</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> </span><span style="color:#676E95;font-style:italic;">// {a:1}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">        o</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">a </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">2</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#82AAFF;">setTimeout</span><span style="color:#A6ACCD;">(</span><span style="color:#89DDFF;">()</span><span style="color:#A6ACCD;"> </span><span style="color:#C792EA;">=&gt;</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">o</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">a</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">=</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">10</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">},</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">3000</span><span style="color:#A6ACCD;">)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(o)</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> </span><span style="color:#676E95;font-style:italic;">// {a:2}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span><span style="color:#A6ACCD;"> </span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">};</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o1 </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> o</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        o</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">a </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">10</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">   </span><span style="color:#676E95;font-style:italic;">// 找到o里面的进行更改</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(o1)</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">	</span><span style="color:#676E95;font-style:italic;">// {a : 10}</span></span>
<span class="line"></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">function</span><span style="color:#A6ACCD;"> </span><span style="color:#82AAFF;">fn</span><span style="color:#89DDFF;">(</span><span style="color:#A6ACCD;font-style:italic;">o1</span><span style="color:#89DDFF;">)</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">            </span><span style="color:#A6ACCD;">o1</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">=</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">{</span><span style="color:#F07178;"> a</span><span style="color:#89DDFF;">:</span><span style="color:#F07178;"> </span><span style="color:#F78C6C;">10</span><span style="color:#F07178;"> </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#F07178;">        </span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span><span style="color:#A6ACCD;"> </span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">};</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#82AAFF;">fn</span><span style="color:#A6ACCD;">(o)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(o)  </span><span style="color:#676E95;font-style:italic;">// a: 1</span></span>
<span class="line"></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br><span class="line-number">10</span><br><span class="line-number">11</span><br><span class="line-number">12</span><br><span class="line-number">13</span><br><span class="line-number">14</span><br><span class="line-number">15</span><br><span class="line-number">16</span><br><span class="line-number">17</span><br><span class="line-number">18</span><br><span class="line-number">19</span><br><span class="line-number">20</span><br><span class="line-number">21</span><br><span class="line-number">22</span><br></div></div></li><li><p>JSON相关</p><ul><li><p>JSON.stringify()</p><ol><li>用于解析成 JSON 对象的 parse()；</li><li>用于将对象转换为 JSON 字符串方法的 stringify()。</li></ol></li><li><p>JSON.parse</p><ol><li><p>将一个 JSON 字符串转换为对象。</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> obj </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span><span style="color:#A6ACCD;"> </span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">};</span></span>
<span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> str </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> JSON</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">stringify</span><span style="color:#A6ACCD;">(obj)</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(str)    </span><span style="color:#676E95;font-style:italic;">// {&quot;a&quot;:1}</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br></div></div></li><li><p>JSON.parse(text[, reviver])</p><p>**text:**必需， 一个有效的 JSON 字符串。</p><p><strong>reviver:</strong> 可选，一个转换结果的函数， 将为对象的每个成员调用此函数。</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#A6ACCD;">        </span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> s </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&#39;</span><span style="color:#C3E88D;">{&quot;a&quot;:10}</span><span style="color:#89DDFF;">&#39;</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#A6ACCD;">        console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(JSON</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">parse</span><span style="color:#A6ACCD;">(s))</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;"> </span><span style="color:#676E95;font-style:italic;">// {a: 10}</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br></div></div></li></ol></li></ul></li></ul></li><li><p>构造函数实例化创建</p><ul><li>var o=new Object()</li></ul></li><li><p>以某个对象为原型创建一个新对象</p><ul><li>var o=Object.create({})</li></ul></li></ul><h4 id="遍历对象" tabindex="-1">遍历对象 <a class="header-anchor" href="#遍历对象" aria-hidden="true">#</a></h4><ul><li><p>for..in.</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> obj </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">{</span><span style="color:#A6ACCD;"> </span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#F07178;">e</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">2</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">2</span><span style="color:#89DDFF;">&quot;</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">3</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#F07178;">c</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">3</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#F07178;">d</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">4</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">1</span><span style="color:#89DDFF;">&quot;</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">0</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">1a</span><span style="color:#89DDFF;">&quot;</span><span style="color:#89DDFF;">:</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">10</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">&quot;</span><span style="color:#F07178;">1b</span><span style="color:#89DDFF;">&quot;</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">20</span><span style="color:#A6ACCD;"> </span><span style="color:#89DDFF;">};</span></span>
<span class="line"><span style="color:#A6ACCD;">obj</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">b </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">3</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">	</span><span style="color:#676E95;font-style:italic;">// 往里面添加b这个属性名</span></span>
<span class="line"><span style="color:#A6ACCD;">obj[</span><span style="color:#89DDFF;">&quot;</span><span style="color:#C3E88D;">11</span><span style="color:#89DDFF;">&quot;</span><span style="color:#A6ACCD;">] </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">4</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">  </span><span style="color:#676E95;font-style:italic;">// 往里面添加11这个属性名</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> a </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#82AAFF;">Symbol</span><span style="color:#A6ACCD;">()</span><span style="color:#89DDFF;">;</span><span style="color:#A6ACCD;">	</span></span>
<span class="line"><span style="color:#A6ACCD;">obj[a] </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> </span><span style="color:#F78C6C;">10</span><span style="color:#89DDFF;">;</span></span>
<span class="line"><span style="color:#89DDFF;font-style:italic;">for</span><span style="color:#A6ACCD;"> (</span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> key </span><span style="color:#89DDFF;">in</span><span style="color:#A6ACCD;"> obj) </span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#F07178;">(</span><span style="color:#A6ACCD;">key</span><span style="color:#89DDFF;">,</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">obj</span><span style="color:#F07178;">[</span><span style="color:#A6ACCD;">key</span><span style="color:#F07178;">])</span></span>
<span class="line"><span style="color:#89DDFF;">}</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br></div></div><blockquote><p>对象遍历</p><ol><li>首先先遍历隐士转换后是数值的属性名,按照从小到大的顺序遍历</li><li>在按照属性名添加的先后顺序遍历</li><li>for...in 无法遍历Symbol类型属性</li></ol></blockquote></li></ul><h4 id="对象的复制" tabindex="-1">对象的复制 <a class="header-anchor" href="#对象的复制" aria-hidden="true">#</a></h4><ul><li>浅复制:只能复制第一层,如果出现引用层,那么无法复制</li><li>实现方式: <ol><li>Object.assign({}, obj)</li><li>Array.prototype.concat() 或者 slice 都是浅复制</li></ol></li></ul><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o</span><span style="color:#89DDFF;">={</span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">,</span><span style="color:#F07178;">b</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">2</span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o1</span><span style="color:#89DDFF;">={}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#89DDFF;font-style:italic;">for</span><span style="color:#A6ACCD;">(</span><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> key </span><span style="color:#89DDFF;">in</span><span style="color:#A6ACCD;"> o)</span><span style="color:#89DDFF;">{</span></span>
<span class="line"><span style="color:#F07178;">    </span><span style="color:#A6ACCD;">o1</span><span style="color:#F07178;">[</span><span style="color:#A6ACCD;">key</span><span style="color:#F07178;">] </span><span style="color:#89DDFF;">=</span><span style="color:#F07178;"> </span><span style="color:#A6ACCD;">o</span><span style="color:#F07178;">[</span><span style="color:#A6ACCD;">key</span><span style="color:#F07178;">]</span></span>
<span class="line"><span style="color:#89DDFF;">}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">o</span><span style="color:#89DDFF;">.</span><span style="color:#A6ACCD;">a</span><span style="color:#89DDFF;">=</span><span style="color:#F78C6C;">10</span></span>
<span class="line"><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(o1)</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br><span class="line-number">7</span><br><span class="line-number">8</span><br><span class="line-number">9</span><br></div></div><ul><li><p>深复制</p></li><li><p>实现方式:</p><ol><li>json.stringfiy 和 parse</li><li>手写递归</li><li>loadash函数库</li></ol><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o</span><span style="color:#89DDFF;">={</span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">,</span><span style="color:#F07178;">b</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">2</span><span style="color:#89DDFF;">,</span><span style="color:#F07178;">c</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">3</span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o1</span><span style="color:#89DDFF;">={</span><span style="color:#F07178;">d</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o2</span><span style="color:#89DDFF;">={</span><span style="color:#F07178;">e</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">10</span><span style="color:#89DDFF;">,</span><span style="color:#F07178;">b</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">20</span><span style="color:#89DDFF;">}</span></span>
<span class="line"></span>
<span class="line"><span style="color:#A6ACCD;">Object</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">assign</span><span style="color:#A6ACCD;">(o1</span><span style="color:#89DDFF;">,</span><span style="color:#A6ACCD;">o)	</span><span style="color:#676E95;font-style:italic;">// 浅复制</span></span>
<span class="line"><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(o1)</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br></div></div></li></ul><h4 id="内存泄漏与垃圾回收" tabindex="-1">内存泄漏与垃圾回收 <a class="header-anchor" href="#内存泄漏与垃圾回收" aria-hidden="true">#</a></h4><ul><li><p>null的作用就是去掉标识</p><div class="language-js line-numbers-mode"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki material-palenight"><code><span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o</span><span style="color:#89DDFF;">={</span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">1</span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#C792EA;">var</span><span style="color:#A6ACCD;"> o1 </span><span style="color:#89DDFF;">=</span><span style="color:#A6ACCD;"> o</span></span>
<span class="line"><span style="color:#A6ACCD;">o1 </span><span style="color:#89DDFF;">=null</span></span>
<span class="line"><span style="color:#A6ACCD;">o</span><span style="color:#89DDFF;">=null</span></span>
<span class="line"><span style="color:#A6ACCD;">o</span><span style="color:#89DDFF;">={</span><span style="color:#F07178;">a</span><span style="color:#89DDFF;">:</span><span style="color:#F78C6C;">2</span><span style="color:#89DDFF;">}</span></span>
<span class="line"><span style="color:#A6ACCD;">console</span><span style="color:#89DDFF;">.</span><span style="color:#82AAFF;">log</span><span style="color:#A6ACCD;">(o)</span></span>
<span class="line"></span></code></pre><div class="line-numbers-wrapper" aria-hidden="true"><span class="line-number">1</span><br><span class="line-number">2</span><br><span class="line-number">3</span><br><span class="line-number">4</span><br><span class="line-number">5</span><br><span class="line-number">6</span><br></div></div></li></ul><h3 id="函数" tabindex="-1">函数 <a class="header-anchor" href="#函数" aria-hidden="true">#</a></h3><h4 id="函数的创建" tabindex="-1">函数的创建 <a class="header-anchor" href="#函数的创建" aria-hidden="true">#</a></h4><ul><li><ol><li>命名函数 -- 使用function 函数名()</li><li>匿名函数 -- var 函数名 = function()</li><li>自执行函数 -- (function() { })( )</li><li>构造函数创建函数 -- var 函数名 = new Funciton(...参数,函数体)</li></ol></li></ul><h5 id="命名函数" tabindex="-1">命名函数 <a class="header-anchor" href="#命名函数" aria-hidden="true">#</a></h5><ul><li>书写函数创建表格</li></ul></div></div></main><!--[--><!--]--><footer class="VPDocFooter" data-v-cfb513e0 data-v-21f75714><!----><div class="prev-next" data-v-21f75714><div class="pager" data-v-21f75714><!----></div><div class="pager" data-v-21f75714><a class="pager-link next" href="/docs/frontend/html/" data-v-21f75714><span class="desc" data-v-21f75714>Next page</span><span class="title" data-v-21f75714>html基础</span></a></div></div></footer><!--[--><!--]--></div></div></div></div></div><footer class="VPFooter has-sidebar" data-v-5211c0b1 data-v-9f24cc86><div class="container" data-v-9f24cc86><p class="message" data-v-9f24cc86>Released under the MIT License.</p><p class="copyright" data-v-9f24cc86>Copyright © 2019-present Evan You</p></div></footer><!--[--><!--]--></div></div>
    <script>__VP_HASH_MAP__ = JSON.parse("{\"frontend_html_标签学习.md\":\"193ebed7\",\"frontend_index.md\":\"6948a9a0\",\"about_index.md\":\"b2600144\",\"frontend_html_index.md\":\"e69c2f61\",\"frontend_js_循环结构.md\":\"28b8fe07\",\"test.md\":\"05afc863\",\"frontend_js_分支结构.md\":\"4da0d0ce\",\"frontend_js_函数（下）.md\":\"65d16cef\",\"frontend_qf_js函数.md\":\"7b4e3856\",\"frontend_css_index.md\":\"dbc2ae4b\",\"frontend_qf_jsdom.md\":\"1e7bc25a\",\"frontend_js_javascript的基础语法.md\":\"cca245cd\",\"frontend_qf_js事件.md\":\"cb54c13e\",\"frontend_js_函数(上).md\":\"8f2f4f7a\",\"frontend_js_dom（下）.md\":\"2ffcc219\",\"index.md\":\"42536bfb\",\"frontend_js_字符串的操作.md\":\"6c33ae72\",\"frontend_qf_js路由.md\":\"a855dc90\",\"frontend_qf_js循环对象.md\":\"79b4e37f\",\"frontend_js_bom和dom（上）.md\":\"4a787030\",\"frontend_js_math和date.md\":\"8f97ac23\",\"frontend_js_数组.md\":\"486283e0\",\"frontend_qf_js对象.md\":\"cfe6c75f\",\"frontend_qf_js运算符.md\":\"79deba5a\",\"frontend_qf_js数组重构.md\":\"0d6ee409\",\"frontend_qf_js数组重构2.md\":\"1bf7162a\"}")</script>
    <script type="module" async src="/docs/assets/app.c4198e49.js"></script>
    
  </body>
</html>